Carburetor



July 26,1927.

A. L. NLSSON CARBURETOR Filed March 8, 1923 Zivil wir.

Patented July 26, 1927.

" UNITED STATES PATENT oFFicE.

AUGUST LEANDER NILSSQN, 0F SODERTALJE, SWEDEN.

CABBURETOR.

Application llled March 8, 1923, Serial No. 623,789, and in Swedenltarch 4, 1922.

On closel'y inspecting and testing the carburetors of internal combustion engines as heretofore used, it has been found that the proportions between fuel and air, when pass- 4ing the motor from no-load running over to partial-load running and, further, to fullload running, have not been the most suitable, in spite of great care having been taken to bring about an adequate adjusting means for the said purpose. This particularly holds good in respect of the carburetor types now mostly used, andvwhich are provi ed with a Venturi tube and with a common throttling device in the air passage. These carburetors truly consist of two such units built together, one being "provided for noload running and one for Voperation under load.

An arrangement whereby the ambunts of fuel will be accurately adjusted to all transitions, loads and speeds, has been brought about by virtue of the presentv invention.

The invention is principally distinguished by the main orifice of the carburetor being divided in two or more nozzles situated in series behind each other, said orifices communicating partly with one another and partly with the no-load orifice of the carburetor in such manner that, on a sucking action taking place through the .first mentioned orifices, there will be produced a vacuum between them which, as far as may be required, is caused to impede the fuel delivered to the nov-load orifice, and which vacuum will thus be determinative of the amount of fuel delivered to the no-loadorilice.v

The amount of such fuel always correi, sponding to the load of the motor prevailin for the time being may be simply brought about bysuitably dimensioning the different main orifices relatively to each other.

The accompanying drawing illustrates an embodiment of the invention. Fig. l is a vertical section of a carburetor devised in accordance with the invention, and Fig. 2 is a section on .line 2-.-2 in Fig. l. ,Fig 3 discloses a modified embodiment.

The sections of the passages of the main orifices must always be so adjusted relatively to eac-h other that they will in each` case admitA the requisite amount of fuel Vwhich always has to primarily pass through the main orifice situated first 1n the series,

and then through theother orifice or the other orifices. t, According to the drawing, there are two main orifices 1 and 2 arranged in series in such .manner that the fuel from the con tainer 14 will first pass' through orifice 1 and then through orifice 2, whereupon the fuel enters the space between the sleeves 9 and 15 whence it passes through the apertures 10 to the channel 16, from which the fuel is discharged through the openings 17 into the air passage or Venturi tube 6. The main orifices 1 and 2 communicate through the connecting passage 3 with the no-load orifice 5. The amount of fuel discharged through the latter asses through the channel 4 to the no-loari) outlet 7, or to the partial-load outlet 8, or to both.

The velocity of the fuel through theV noload orifice 5 is dependent on the fall of pressure between the connecting passage 3 and the 11o-load channel 4. Therefore, by changing the vacuum in the connecting passage, the delivery of fuel to the no-load channel 4 and thus to the partial-load outlet 8y maybe caused to decrease at a higher or lower rate, while the throttle device 18 is being opened. The amount of fuel from the partial-load Voutlet 8 may thus be adjusted to the delivery from theI mam outlet 17, sothat the mixture will be the proper` one also at times when both outlets are delivering simultaneously.

The arrangementaof orifices as described hereinabove may be carried out so that the main orifices 1 and 2 aswell as the no-load orifice 5 are mounted in a special shell 9 adapted to be removed, and which is provided with outlet openings, partly 10 from the main orifice, and partly 11 from the noload nozzle. Air is admitted from the well 20 through certain openings 12 and 13 in the said shell, such air effecting the first atomizatin of the fuel.

The device may be disposed 'either in a lateral channel opening into the narrowest portion of' the main passage, or, it may be mounted in the latter direct.

WhatI claim as new and desire to secure by Letters Patent of the United States of p America is said well, a fuel su ply 'duct leading to said orifice, a, sleeve wit said Well frmin a chamber at the bottom thereof for which the orifice is an inlet' and having a restriction within its bore, said restriction admitting fuel from said chamber to said sleeve, a second sleeve around said first sleeve and spaced yto provide a normal fuel passage be= tween said sleeves, an outlet from said chamber-to said normal fuel passage, ports in said second sleeve communicating with said air duct, a port 'leading from said air duct to said first sleevez and a duct leading from said sleeve to sald induction tube:

In testimony whereof l afx my signature' AUGUST LEANDER NI'LSSON. 

